[Alex@Raspi.tv] had the misfortune of blowing the USB hub and Ethernet port on a Raspberry Pi B+. He thought about using a cheap SPI to Ethernet board to rescue it, and while he bought the board, he never got around to interfacing it to the broken Pi. However, when he saw the Raspberry Pi Zero arrive and noticed that everyone wanted to connect it to the network, he remembered the SPI board, rescued it from his junk box, and a few hours later had Ethernet via Raspberry Pi GPIO working.
To make things easier, he got it all working on a Pi A first and then moved to the Zero. You’d think performance would not be very good, but measurements [Alex] made show it isn’t bad at all, considering:
Pi Zero at 12 MHz 3.33 Mbaud down, 2.82 Mbaud up, 39.956 ms latency, 52.19km
Pi Zero at 16 MHz 3.67 Mbaud down, 2.90 Mbaud up, 37.749 ms latency, 43.57km
Pi Zero at 20 MHz 3.88 Mbaud down, 3.10 Mbaud up, 42.474 ms latency, 43.57km
[Alex] notes that the Pi’s official 3.3V rail capacity doesn’t meet the requirements of the SPI Ethernet module he used. However, he also says it works, and he’s heard “unofficially” that it probably should work. We were not sure if he meant he heard the Pi’s 3.3V supply is underrated or if the consumption of the Ethernet chip is overstated.
We’ve seen a lot of Pi Zero hacks in the last week or two. The WiFi hack is similar, and there was an audio hack, too. Of course, there’s also the lively debate about if you should try to extend a Zero anyway.